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Space elevators are one of those technologies that sci-fi nerds like me obsess over.

They straddled the line between outlandish impossibility and engineering potential.

A space elevator is a giant elevator shaft that we can climb to reach space.

It's a technology that could cross the divide of science fiction to science reality if we somehow improved on existing technologies.

We will use steel but with more realistic material properties.

Steel is one of the strongest materials we have, but we do have less dense materials which will reduce the tensile stress we have to endure.

We can calculate the Max tension in the cable with a uniform cross section with this equation, where G is the gravitational constant, M is the mass of the Earth , rho is the density of our material of choice.

The amount of material required to build something like this would outstrip any cost savings we could possibly supply.

Kevlar and carbon fibre are looking a lot better. They will have a circular diameter of 80 meters and 170 meters respectively. Still not quite feasible.

We will revisit this subject with a design investigation for an actual space elevator using this theoretical material.